 The Win32 subsystem shown next to the POSIX and OS/2 subsystem in the architecture of Windows NT (later Win64 is also available.) | |
| Developer(s) | Microsoft |
|---|---|
| Initial release | November 20, 1985 |
| Operating system | Microsoft Windows, OS/2 |
| Predecessor | DOS API |
| Type | API |
| License | Proprietary |
| Website | https://learn.microsoft.com/en-us/windows/apps/ |
The Windows API, informally WinAPI, is the foundational application programming interface (API) that allows a computer program to access the features of the Microsoft Windows operating system in which the program is running. Programs access API functionality via dynamic-link library (DLL) technology.
Each major version of the Windows API has a distinct name that identifies a compatibility aspect of that version. For example, Win32 is the major version of Windows API that runs on 32-bit systems. The name, Windows API, collectively refers to all versions of this capability of Windows.
Microsoft provides developer support via a software development kit, Microsoft Windows SDK, which includes documentation and tools for building software based on the Windows API.